(Cat? OR feline) AND NOT dog?
Cat? W/5 behavior
(Cat? OR feline) AND traits
Cat AND charact*

This guide provides a more detailed description of the syntax that is supported along with examples.

This search box also supports the look-up of an IP.com Digital Signature (also referred to as Fingerprint); enter the 72-, 48-, or 32-character code to retrieve details of the associated file or submission.

Concept Search - What can I type?

For a concept search, you can enter phrases, sentences, or full paragraphs in English. For example, copy and paste the abstract of a patent application or paragraphs from an article.

Concept search eliminates the need for complex Boolean syntax to inform retrieval. Our Semantic Gist engine uses advanced cognitive semantic analysis to extract the meaning of data. This reduces the chances of missing valuable information, that may result from traditional keyword searching.

An Proactive Scanning Approach to Monitoring Object Lifecycle based on Weak Reference

Publishing Venue

IBM

Abstract

This invention provides a method to enable user monitor object’s lifecycle in Object Oriented languages without any modification to languages' runtime environment or the application itself. Compared with traditional approach, the proposed method uses a totally different way that relies on Byte Code Instrumentation and Object Oriented language support (e.g. weak reference) to monitor object’s lifecycle. The key ideas of our invention are A. Combine object's proactive notification with the agent's proactive scanning together to monitor object's lifecycle and usage information. B. Based on Weak Reference to detect object's recycle time. C. An newly designed data structure (ID tag in each object to reference flat one-one mapping tables) that enable very fast notification and scanning of the detection.

Country

Undisclosed

Language

English (United States)

This text was extracted from a PDF file.

This is the abbreviated version, containing approximately
29% of the total text.

Page 1 of 6

An Proactive Scanning Approach to Monitoring Object Lifecycle based on Weak Reference

1. Background

This invention provides a method to enable user monitor object's lifecycle in Object Oriented languages without any modification to languages' runtime environment or the application itself.

The background is that standard object oriented programming practices leads to poor memory usage, which is called software bloat in academic area. For example, in IBM WAS (based on Java, the widely used OO language), there are huge memory usage pressures coming from (1) excessive allocation; (2) allocating objects much sooner than needed; (3) holding objects for too long, memory leaks, which lead to frequent garbage collection. However, bloat and excessive memory use hinder scalability because memory bandwidth is a finite resource in today's hardware system, and long living objects will not only occupy memory space, but also bring pressure to memory recycle, such as GC. We need tools to help user identify bloat.

Bloat includes size bloat and object lifecycle bloat. Lifecycle bloat means the object's living time is much longer than expected. Figure 1 shows the situation. Only the middle part of the object is useful. However, many objects' in OO language such as Java have a lot of objects that have long useless period and leak period.

Object GC

Allocation First use Last use No reference Lag (Useless period) Drag (Leak period)

Solution: lazy load Solution: clear

reference earlier

Figure 1, Object's lifecycle

However, identifying object's lifecycle is always a very difficulty problem, and there are very few practiced methods. Based on our detail survey, known solutions have the following disadvantages1. Only provide statistics information of Object's lifecycle

Example:

JVMTI interface of Java, most commercial memory lifecycle tools are based on it.